Basin-wide variation in tree hydraulic safety margins predicts the carbon balance of Amazon forests

Tropical forests face increasing climate risk1,2, yet our ability to predict their response to climate change is limited by poor understanding of their resistance to water stress. Although xylem embolism resistance thresholds (for example, Ψ50) and hydraulic safety margins (for example, HSM50) are important predictors of drought-induced mortality risk3–5, little is known about how these vary across Earth’s largest tropical forest. Here, we present a pan-Amazon, fully standardized hydraulic traits dataset and use it to assess regional variation in drought sensitivity and hydraulic trait ability to predict species distributions and long-term forest biomass accumulation. Parameters Ψ50 and HSM50 vary markedly across the Amazon and are related to average long-term rainfall characteristics. Both Ψ50 and HSM50 influence the biogeographical distribution of Amazon tree species. However, HSM50 was the only significant predictor of observed decadal-scale changes in forest biomass. Old-growth forests with wide HSM50 are gaining more biomass than are low HSM50 forests. We propose that this may be associated with a growth–mortality trade-off whereby trees in forests consisting of fast-growing species take greater hydraulic risks and face greater mortality risk. Moreover, in regions of more pronounced climatic change, we find evidence that forests are losing biomass, suggesting that species in these regions may be operating beyond their hydraulic limits. Continued climate change is likely to further reduce HSM50 in the Amazon6,7, with strong implications for the Amazon carbon sink

Basin-wide variation in tree hydraulic safety margins predicts the carbon balance of Amazon forests

This is the final version. Available on open access from Nature Research via the DOI in this recordData availability: The pan-Amazonian HT dataset (Ψ 50, Ψ dry and HSM50) and branch wood density per species per site, as well as forest dynamic and climate data per plot presented in this study are available as a ForestPlots.net data package at https://forestplots.net/data-packages/Tavares-et-al-2023. Basal area weighted mean LMA is shown in Supplementary Table 2. Species stem wood density data were obtained from Global Wood Density database65,66. Species WDA data were extracted from ref. 45.Code availability: The codes to recreate the main analyses and the main figures presented in this study are available as a ForestPlots.net data package at https://forestplots.net/data-packages/Tavares-et-al-2023.Tropical forests face increasing climate risk, yet our ability to predict their response to climate change is limited by poor understanding of their resistance to water stress. Although xylem embolism resistance thresholds (for example, Ψ 50) and hydraulic safety margins (for example, HSM50) are important predictors of drought-induced mortality risk, little is known about how these vary across Earth’s largest tropical forest. Here, we present a pan-Amazon, fully standardized hydraulic traits dataset and use it to assess regional variation in drought sensitivity and hydraulic trait ability to predict species distributions and long-term forest biomass accumulation. Parameters Ψ 50 and HSM50 vary markedly across the Amazon and are related to average long-term rainfall characteristics. Both Ψ 50 and HSM50 influence the biogeographical distribution of Amazon tree species. However, HSM50 was the only significant predictor of observed decadal-scale changes in forest biomass. Old-growth forests with wide HSM50 are gaining more biomass than are low HSM50 forests. We propose that this may be associated with a growth–mortality trade-off whereby trees in forests consisting of fast-growing species take greater hydraulic risks and face greater mortality risk. Moreover, in regions of more pronounced climatic change, we find evidence that forests are losing biomass, suggesting that species in these regions may be operating beyond their hydraulic limits. Continued climate change is likely to further reduce HSM50 in the Amazon, with strong implications for the Amazon carbon sink

Action of selective serotonin reuptake inhibitor on aggressive behavior in adult rat submitted to the neonatal malnutrition

The effect of the malnutrition during suckling on the aggressiveness was investigated in adult rats treated or not with citalopram, a selective serotonin reuptake inhibitor (SSRI). The animals were divided into two groups according to the diet used: nourished group- the rats received the control diet with 23% protein during the life; and malnourished group- the rats had its mothers submitted to diet with 7.8% protein during suckling. At 120 days of age, each group was sub-divided according to the treatment: acute - consisting a single i.p. injection of saline solution or 20-mg/Kg citalopram; chronic - consisting the single injections (1 per day during 14 days) of saline or 20 mg/Kg citalopram. The acute or chronic treatment with SSRI reduces aggressive response in nourished rats, but not in malnourished ones. Thus, the malnutrition during the critical period of brain development seems to induce durable alterations in the function of the serotoninergic neurotransmission.593A49950

Risco e segurança sanitária: análise do reprocessamento de produtos médicos em hospitais de Salvador, BA

OBJETIVO: Analisar condições técnicas do reprocessamento de produtos médicos em hospitais. MÉTODOS: Estudo descritivo de casos múltiplos em centros de material e esterilização de quatro hospitais da cidade de Salvador, BA, em 2010. Foram realizadas entrevista semiestruturada e observação direta, com base em modelo regulatório de reprocessamento de produtos médicos elaborado com a técnica de Conferência de Consenso como padrão de referência. As categorias analíticas utilizadas neste estudo foram: gerenciamento da prática de reprocessamento de produtos médicos, protocolos de reprocessamento, monitoramento do processo de esterilização e rastreabilidade de produtos. Essas categorias foram pontuadas segundo sua conformidade com o modelo regulatório de reprocessamento utilizado. RESULTADOS: Observou-se inadequação generalizada das condições técnicas de reprocessamento de produtos médicos, das condições estruturais dos centros de material e esterilização estudados e das condições dos processos de trabalho, além de dificuldades organizacionais e gerenciais que interferiram nas práticas analisadas. CONCLUSÕES: As práticas de reprocessamento dos produtos médicos nos hospitais analisados configuram risco para os pacientes usuários. É necessária a adoção de um sistema de gerenciamento de risco nesses hospitais e de maior controle sanitário pelo Estado, a fim de proteger a saúde dos pacientes

Amyotrophic lateral sclerosis in Brazil: 1998 national survey Esclerose lateral amiotrófica no Brasil: registro nacional, 1998

OBJECTIVES: To assess the epidemiologic characteristics of amyotrophic lateral sclerosis (ALS) in Brazil in 1998. METHOD: Structured Clinical Report Forms (CRFs) sent to 2,505 Brazilian neurologists from January to September 1998 to be filled with demographic and clinical data regarding any ALS patient seen at any time during that year. RESULTS: Five hundred and forty CRFs were returned by 168 neurologists. Data on 443 patients meeting the criteria of probable or definite ALS according to El Escorial definition were analysed: 63 probable (14.2%) and 380 definite (85.8%). Two hundred and fifty-nine (58.5%) of the patients were male, mean age of onset was 52. Spinal onset occurred in 306 patients (69%); bulbar onset in 82 (18.5%), and both in 52 (11.7%). Twenty-six (5.9%) had a family history of ALS. Two hundred and fifty-nine (58.6%) were seen by private practitioners, and 178 (40.2%) at a hospital clinic. Age-ajusted incidence shows a peak incidence at the 65-74 years old range. CONCLUSIONS: The disease's characteristics are similar to those described in international studies, except for age of onset (Brazilian patients are younger). This difference is not confirmed when figures are age-adjusted.<br>OBJETIVOS: Avaliar as características epidemiológicas da esclerose lateral amiotrófica (ELA) no Brasil durante o ano de 1998. MÉTODO: Formulários estruturados enviados a 2.505 neurologistas brasileiros de janeiro a setembro de 1998 para serem preenchidos com dados demográficos e clínicos de todos os pacientes com ELA atendidos no ano de 1998. RESULTADOS: Quinhentos e quarenta formulários retornaram, enviados por 168 neurologistas. Dados sobre 443 pacientes que se enquadravam nos critérios de ELA provável ou definida de acordo com El Escorial foram analisados: 63 provável (14,2%) e 380 definida (85,8%). Duzentos e cinquenta (58,5%) eram do sexo masculino. A idade média de aparecimento dos primeiros sintomas foi de 52 anos. O início em membros ocorreu em 306 pacientes (69%), bulbar em 82 (18,5%) e generallizada em 52 (11,7%). Vinte e seis (5,9%) tinham história familiar. Duzentos e cinquenta e nove (58,6%) foram atendidos em clínicas ou consultórios, e 178 (40,2%) em ambulatório de hospital. Ajustando para a distribuição da população brasileira segundo faixa etária, a maior incidência ocorre entre 65 e 74 anos de idade. CONCLUSÕES: As características epidemiológicas da doença são semelhantes àquelas descritas em estudos internacionais, exceto para idade dos primeiros sintomas (pacientes brasileiros são mais jovens). Esta diferença desaparece quando os valores são ajustados para idade